Density functional study of structural and electronic properties of cube-like MgO clusters

The structural and electronic properties of neutral cube-like MgO clusters comprising of 8, 18, 32, 48 and 64 atoms have been studied using density functional theory. Geometry optimization of all these stoichiometric clusters was done with C2v symmetry. The binding energy and the nearest-neighbor separation in these clusters show a progressive approach towards their corresponding bulk values. The densities of states indicate an increase in the width of valence bands with increasing cluster size. Total charge density plots show a relatively stronger dependence of magnesium charge density on the coordination number as compared to that of oxygen in the 64-atom cluster.